0

我有一个看起来像这样的模型：

class Mentorship (models.Model):
    mentor = models.ForeignKey(settings.AUTH_USER_MODEL, related_name='mentor_user_id')
    mentee = models.ForeignKey(settings.AUTH_USER_MODEL, related_name='mentee_user_id')

    objects = MentorshipManager()

    def clean(self):
        print(self.mentor_id)  # is set and printed to stdout
        print(self.mentee_id)  # is set and printed to stdout

        if Mentorship.objects.is_mentor(self.mentor_id, self.mentee_id):
            raise ValidationError(_('This user is already a mentor.'))

manager 有一个函数来检查某人是否已经是另一个用户的指导者，在clean()ing 实例时调用该函数：

def is_mentor_for_goal(self, mentor_id, mentee_id, personal_goal_id):
    if self.exists(mentor_id=mentor_id, mentee_id=mentee_id):
        return True
    else:
        return False

mentor_id但是，在访问存在的ormentee_id属性时，我总是遇到异常：

Django Version:     1.6.1
Exception Type:     TypeError
Exception Value:    exists() got an unexpected keyword argument 'mentor_id'

我无法访问管理器中的 _id 字段是否有原因？我只是不明白为什么在（未保存的）实例中可以访问该字段，但在管理器中却不能。

4

2 回答 2

2

哦……伙计……应该叫

if self.filter(mentor_id=mentor_id, mentee_id=mentee_id).exists()

感谢您的意见

于 2014-03-06T12:20:24.983 回答
0

有些事情mentor__id只适用于查询集方法，而不是像print. 您还应该使用pk而不是id，这是它的工作原理：

class Mentorship(models.Model):
    mentor = models.ForeignKey(settings.AUTH_USER_MODEL, related_name='mentor_user_id')
    mentee = models.ForeignKey(settings.AUTH_USER_MODEL, related_name='mentee_user_id')

    objects = MentorshipManager()

    def clean(self):
        print(self.mentor.pk)  # is set and printed to stdout
        print(self.mentee.pk)  # is set and printed to stdout

        if Mentorship.objects.filter(mentor=self.mentor).exists():
            raise ValidationError(_('This user is already a mentor.'))

def is_mentor_for_goal(self, mentor_id, mentee_id, personal_goal_id):
    return self.exists(mentor__pk=mentor_id, mentee__pk=mentee_id)
于 2014-03-06T12:23:58.020 回答